Depth specialization in mesophotic corals and associated algal symbionts in Hawai‘i

Abstract

Corals at the lower limits of mesophotic habitats are likely to have unique photosynthetic adaptations that allow them to persist and dominate in these extreme low light ecosystems. We examined the host–symbiont relationships from the dominant coral genusLeptoserisin mesophotic environments from Hawai‘i collected by submersibles across a depth gradient of 65 – 125m. Coral andSymbiodiniumgenotypes were compared with three distinct molecular markers including coral (COX1–1-rRNA intron) and Symbiodinium(COI) mitochondrial markers and nuclear ITS2.